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View Full Version : How much can a boolit be sized down?



njc110381
03-12-2019, 05:33 PM
Hi guys. Do you think it would be possible to swage a .430 boolit down to .417 if it was made of a fairly soft alloy? I'm thinking of trying to use a Lee .430 mold to cast for my .416 Rigby...

Conditor22
03-12-2019, 05:41 PM
you could, I would recommend doing it in increments. I recently went down .008 in one pass (15bhn) using a cheater bar. The boolits came out OK. you could try and see if the boolit isn't too deformed. My 2¢

Outpost75
03-12-2019, 07:43 PM
Would be easier to get a .410 mold and make a hammer swage to bump it up.

country gent
03-12-2019, 11:22 PM
.430 to .417 is .023 you will loose most of the lube grooves if not all of them sizing down this much. Another issue with sizing this much will be the force required and keeping bases square and free from fins. The last will be if there is a bore riding section of the nose it will need sized down also.

Better would be to have Noe or accurate cut a .41 cal mould large or look at bullets made for the rifle of the desired weight range. This would get a good mould ready to go. To size and form weight desired

Last would be the 41 cal mould in size and shape and lap it out to what you need. these moulds are in the .410-.412 dia and it would be some hand work to do but one could be lapped or leemented to .417. This would give you a dedicated mould and less issues than trying to size down.

It is possible to size a bullet down that much but in reality it becomes more a swaging operation than a sizing operation. Along with the resulting increases in pressures.

Another way to go is to use the 41 cal bullet and bump up to the required .418 size in a press. a die and ejector made to match the bullet with a close fitted pusher. insert bullet and cycle the press swelling the bullet to match the dies sizes. Bullet will get shorter but nose and driving bands can be maintained easier.

megasupermagnum
03-13-2019, 01:16 AM
.430" to .417" is a difference of .013". It's a jump, but not unheard of. If you size down in two steps, you will have a much better result. Unfortunately the cost of two custom Lee sizers is about the same as a custom bullet mold, so unless you make your own sizers, it doesn't do you much good.

Conditor22
03-13-2019, 02:32 AM
417 sizer http://noebulletmolds.com/NV/product_info.php?cPath=104_404&products_id=2668

you could get the 419 had sand it out a few sizes bigger to be the intermediary sizer.

Bazoo
03-13-2019, 03:23 AM
I have sized .008 before and it made the lube grooves inconsistent. When I sized in 2 stages it was okay. I'd suggest 3 stages minimum. Accuracy won't be great I'll bet because sizing that much will have to swage the driving bands more on one side than the other and the resultant bullet will be out of balance.

njc110381
03-13-2019, 03:41 AM
Thanks guys. I think if I'm pushing my luck with it I may as well get a proper mould to start with. They're just quite expensive for the .416 Rigby - or rather I can't get a cheap Lee in that size. I'll just buy the RCBS .416-350RN. I keep finding them second hand on Ebay but nobody in the states seems to want to post them to me. I guess it must be a restricted part? It's a shame, they're about £120 here - $160US! We pay a premium for everything!

I'm planning to hone out a Lee .410 sizer to seat the gas checks. I don't really want to spend the money on a Lubrisizer having had to buy a bigger press for the Lee crimp die already!

David2011
03-13-2019, 04:31 AM
A commercial caster I know accidentally ran a .452 boolit through the .430 die using an automated air powered Star. Said he didn't recommend it, though. It came out much longer than it went in and there wasn't much left of the loob grooves.

Traffer
03-13-2019, 05:32 AM
You could roll it between two flat steel plates with a pin of .417" diameter as a stop. Softer lead will roll fairly easily. I mean with maybe 20 lbs of pressure. It would squish the lube grooves but any way you size it down it will do that. Or if you have a lathe, you can make a swaging die with a taper going from .430 to ,417" and have the last space that is as long as your bullet be all at .417"
The trick to swage down stuff is to polish the inside of the die to a mirror bright shine And use case lube. Then it wouldn't be hard at all. No cheater bar necessary.

KCSO
03-13-2019, 08:13 AM
I had no problem sizing a 324 bullet to 316 fro my 303. I used a couple of push throughs to go a step at a time and then sized and lubed in a Lyman 45.

sharps4590
03-13-2019, 08:15 AM
I've not taken one down that much but one thing I see missing. If you lube the bullet first you won't lose quite so much of the lube grooves and I believe the driving bands will remain consistent. I take some .323's down to .318 and if lubed first the grooves and driving bands certainly appear to stay pretty much the same and equal. I size something else down either .008 or .010 but I can't remember what it is. Admittedly neither is .013 but at .010, it's close. I think I'd give it a whirl just to see what happened.

Traffer
03-13-2019, 11:55 AM
I've not taken one down that much but one thing I see missing. If you lube the bullet first you won't lose quite so much of the lube grooves and I believe the driving bands will remain consistent. I take some .323's down to .318 and if lubed first the grooves and driving bands certainly appear to stay pretty much the same and equal. I size something else down either .008 or .010 but I can't remember what it is. Admittedly neither is .013 but at .010, it's close. I think I'd give it a whirl just to see what happened.

Good point about the lube. I think that means put some good thick grease well into the grooves before sizing ...that will keep the grooves from collapsing.

donald duck
05-13-2019, 03:49 PM
My H & R Mag Barrel for my Contender is .308. I purchase .312 bullets and run through a Lee sizer die to .309. They shoot nice in my Contender H & R Msg and my 30-30. In the .32 H & R mag they are very accurate at 25 yds. DD

fredj338
05-14-2019, 12:52 PM
I have sized jacketed 300gr/0.429 down to 0.423 for shooting in my 404 jeffery with good results. I use a 0.427" sizer then a 0.423". I get 2" groups at 100y which is plenty good for practice to 200. I think it is a bit of a crunch to go all the way to 0.417.

swisscast
05-14-2019, 02:44 PM
I’ve got a similar task sizing cast .430 bullets down to .415 for use in 10.3x60R (.450/400 2 3/8“ Nitro Express), which is still quite popular in Switzerland. NOE C432-265 RF, MP C434-215 SWC, MP C429-244 SWC, Lee C429-240 SWC and Lee C430-310 RF are all sized in two steps with Lee push through sizers. Starting with a .429 to seat the gas check, followed by a .410 enlarged to .415. Did this in the past sometimes with the lube grooves filled to prevent deformation, as seen on the pictured Lee C430-310 RF.

Nowadays I don’t bother with lube anymore and just PC the bullets after the final sizing. Alloy hardness ranges from 8 to 18 HB. The harder ones require a bit more pressure for the second stage. The partial loss of the lube grooves seems not to be a problem. I’m very happy with the accuracy of these bullets – consistently achieving sub 2 MOA five shot groups on top of mild loads of 20grs N110 in a single shot hunting rifle based on a K31 System.

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